I ended up deleting my user prefs tonight as 2009 started 'not recognizing' mentalray and actually crashed when I tried manually loading the plugin...nice. I'll give it a little more play but at this point, I'd be more than a little nervous starting a large project with it. We'll see. There are a few modeling tests I did before that would cause it to crash so I'll continue and see if it's still acting squirrely or if deleting the user prefs solved any issues I was having.
"Terminat Bora Diem, Terminal Auctor opus."